Combined mixer and conveyor unit for granular, powdered or like materials



A nl 6, 1965 e. ClANl ETAL 3,176,377

COMBINED MIXER AND CONVEYOR UNIT FOR GRANULAR, POWDERED OR LIKE MATERIALS Filed D60. 27, 1962 2 Sheets-Sheet l April 6, 1965 Filed Dec. 27, 1962 G. CIANI ETAL 3,176,877 COMBINED MIXER AND CONVEYOR UNIT FOR GRANULAR, POWDERED OR LIKE MATERIALS 2 Sheets-Sheet 2 United States Patent Ofiice 3,176,877 Patented Apr. '6, 1 965 This invention relates generally to a combined mixer and "conveyor unit for granular, powdered or likema- .terial hereinafter referred to as the princ1pal material,

and -more specifically to a mixer for mixing foundry sand, the principal material, with a core binder and an accelerator, hereinafter referred to as additives, in order toprovide a mixture for use with the cold setting of .foundry cores.

The recent development ofthe cold setting core binders-enables core boxes to be filled and left to set at room :temperature and the setting time can be controlled by the amount of accelerator used. The normal practice in foundries is for the sand, binder and accelerator to be mixed in some suitable mixer and to be then conveyed possibly by a barrow to the station where the core boxes are being filled. The setting time is therefore governed by the delay which may occur between discharging the material from the mixer and the actual filling of the core box, for obviously if a high proportion of the accelerator is used the mixed sand may set before it has been rammed into the core box.

From the point of view of the foundry it is desirable that the setting time should be as short as possible and it is therefore a specific object of the present invention to provide a mixer which will enable a high proportion of accelerator to be used and thus the achievement of a short setting time.

It is a further object of the present invention to provide an apparatus for mixing sand and an additive which includes a screw-type conveyor contained within a housing which can be swung with respect to a supporting frame to alter the position of discharge of mixed materials from said conveyor so as to facilitate the distribution of the mixed materials in a core box.

It is a still further object of the present invention to provide an apparatus for mixing sand and a binding material in which operation of the apparatus is under the control of a single operator who is able to maintain a constant check on the discharge of mixed materials into a core box and to stop and start said discharge when required without interrupting his constant check or moving away from the core box.

One construction according to the invention is diagrammatically illustrated by way of example in the accompanying drawing wherein:

FIGURE 1 shows a front elevation of a combined mixer and conveyor unit,

FIGURE 2 shows a plan view of the combined mixer and conveyor unit, and

FIGURE 3 shows a side elevation of the combined mixer and conveyor unit.

A combined mixer and conveyor unit for foundry sand includes a screw-type conveyor 11, mounted in a horizontally extended housing 12, the screw being provided with formations which will assist in the mixing of the material, or alternatively, the screw being interrupted at one or more spaced positions and suitable mixing paddles being secured to the shaft of the screw at such positions. The housing 12 is supported adjacent the. one end thereof upon a suitable bed or frame 13, the arrangement being that-housing 12canbeswung about a verticalaxis with respect to frame 13.

Thehousing 12 is secured to a longitudinally extending beam 14 which is itself secured to a downwardly extending stub shaft 15 engaging in. a suitable bearinghousing in the top of frame 13. Also carried by beami1'4 is an electric motor 16 whichis coupled through-a suitable gear box '17 and through .a .suitable flexible coupling 18 to a shaft 19 of the conveyor Adjacent its other end the underside of the housing is cut away to provide a discharge opening 20 and a downwardly extending'bafiie 21 is secured thereto to provide controlled discharge of the material. In between discharge opening .20 and the actual adjacent end of the housing the hand of. the conveyor worm 11 is reversed .so as to ensure that all material is 'dischargedfmm the housing.

Mounted above that end of the housing 12 which is supported by frame '13 and havin'ga suitable shield for guiding materiallinto the'housing is a loading unit 22 which includes, at its. upper end, a sand hopper '23 there being mounted-in hopper :23 adjacent the lower end thereof an adjustable sand gate24 which includes a pair ofapertured plates-25 whereby by ettectingreiative movement between plates 25 the size of the discharge opening from hopper 23, and *thus the rate -.of feed of sand, can be controlled. Additionally sand gatev 24 has asso .ciated therewith 'a closure plate .26 which-can be moved so as to close the opening, the closure plate 26 being op- ;gated through a suitable pneumatic or hydraulic cylinder Leading into the lower end of the hopper, below the sand gate, is a nozzle 28 through which the core binder, which may be in the form of an oil or a resin, can be fed. This core binder is fed from a suitable variable speed pumping unit which can of course be adjusted to give the desired rate of feed and thus the desired proportion between the sand and the binder.

A further feed point 29 may be provided adjacent the lower end of hopper 23 or through the guide between hopper 23 and housing 12, this further feed point 29 being for the reception of an accelerator which is normally in the form of a powder and which can be injected by any suitable mechanism.

Where a resin-acid catalyst system of binder is employed provision is made in the core for the introduction of the liquid catalyst into the sand stream controlled by a suitable variable speed pump. The liquid catalyst is introduced into the partially mixed sand at a point 33 some distance along the mixing trough.

The frame 13 upon which housing 12 is mounted carries a suitable control panel 30. The drive for the conveyor unit, the sand gate, the binder feed and the accelerator feed are all operated through control panel 30 by the medium of STOP and START buttons 31 which are mounted adjacent discharge opening of housing 13. Thus the operator who is filling the core box will have complete control of the machine from his operating position. A handle 32 is provided at the end adjacent discharge opening 20 so that housing 12 can be swung about a vertical axis with respect to frame 13.

In order to ensure that all the mixed sand has been discharged from the machine a suitable time delay circuit is provided so that the conveyor unit will continue operating for a predetermined time after the STOP button has been pressed. In view of the cold setting nature sand and a binding material and then discharging the I mixed materials into a core box comprising:

a 3 of the materials some provision is made in order to prevent the mixed materials setting in the conveyor.

' What we claim then is: i a

1. Apparatus for simultaneously mixing and conveying ing to stop the drive means, the feed means for the sand and the feed means for the additive. 2..-Apparatus according to claim 1 which includes a (a a frame, (b) a housing pivotally mounted upon said frame for sand and an additive comprising: 5 movement about a substantially vertical axis rela- (a) a frame, 1 e 7 tive to said frame, (b) a housing pivotally mounted upon said frame, (c) a screw-type conveyor contained within said (0) a screw-type conveyor contained Within said houshousing, I 7

ing, c i (d) a hopper fixedly supported by said frame and dis- (d) means for feeding sand at a predetermined rate 10 vposed above said conveyor, to one end of said conveyor, (e) means for feeding sand from said hopper to one (e) a discharge nozzle at the other end of the said end of the said conveyor,

conveyor, (f) a discharge nozzle at the other end of said con- (1') means for feeding the additive at a predetermined veyor, e

rate to said conveyor, (g) means for feeding bindingmaterial at a prede- (g)' drive means for said conveyor, termined rate to said conveyor, (h) an operating handle disposed near said discharge (h) an electric motor mounted on said housing for nozzle for swinging saidconveyor and housing reladriving said conveyor, tive'to said frame, r (i) an operating handle disposed near said discharge (i) control means for said apparatus comprising a pair nozzle for swinging said conveyor, housing and mo of manually operable control members disposed near tor about said, substantially vertical axis to facilitate said discharge nozzle, operation of one of the said the distribution of materials discharged from said members serving to start the drive means, the feed discharge nozzle into a core box, and means for the sand and the feed means for the ad- (1') control means for said apparatus comprising a pair ditive and operation of the other said member servof push buttons mounted on said housing and disposed near said discharge nozzle, operation of one of which serves. to stop, and operation of the other serves to start, the drive to said' conveyor, the feed means for the sand and the feedmeans for the binding material.

sand hopper having a'downwardly directed discharge opening mounted upon said frame and disposed above said conveyor, said hopper having a gate which includes:

(a) a pair of'apertured plates for adjusting the size of said discharge opening and thus the rate of feed References Cited in the file of this patent UNITED STATESPATENTS of said from said hopper, and 7 740,699 Schrader Oct. 6, 1903 (b) a closure plate for opening and closing said dis- 1,964,028 Boyntou et al. June 26, 1934 charge opening. 2,162,443 Muller June 13, 1939 3. .Apparatus for simultaneously mixing and conveying 3,005,373 Ransom Oct. 14, 1961 

1. APPARATUS FOR SIMULTANEOUSLY MIXING AND CONVEYING SAND AND AN ADDITIVE COMPRISING: (A) A FRAME, (B) A HOUSING PIVOTALLY MOUTED UPON SAID FRAME, (C) A SCREW-TYPE CONVEYOR CONTAINED WITHIN SAID HOUSING, (D) MEANS FOR FEEDING SAND AT A PREDETERMINED RATE AT ONE END OF SAID CONVEYOR, (E) A DISCHARGE NOZZLE AT THE OTHER END OF THE SAID CONVEYOR, (F) MEANS FOR FEEDING THE ADDITIVE AT A PREDETERMINED RATE TO SAID CONVEYOR, (G) DRIVE MEANS FOR SAID CONVEYOR, 